A compound attribute that is the ratio of amount of protein FAM3B (human) in blood to amount of fibroblast growth factor 19 (human) in blood. The trait is FAM3B/FGF19 protein level ratio in blood (OBA_2055348, an Ontology of Biological Attributes identifier). Also known as: the ratio of amount of protein FAM3B (human) in blood to amount of fibroblast growth factor 19 (human) in blood.